The invention relates to an apparatus for inserting and removing screws, particularly self-tapping screws, with a screwing tool for engaging on a screw head and which is connectable to a drive motor, as well as with an automatic screw supply.
Such apparatuses are used for facilitating frequently repeated screwing processes, in that the screw supply takes place automatically. A preferred field of use is the fixing of roof and wall elements made from sheet metal or other materials, the automatically supplied screws, during insertion, drilling their screw hole and tapping the thread.
Apparatuses have already been proposed in which the screw supply takes place by a plastic strip mechanically indexed by the apparatus and which has cross-like slits through which are placed the screws. During insertion, the screw is torn through this strip and in this way is detached therefrom. However, it frequently occurs that parts of the plastic strip are also torn, become fixed under the screw head or other parts which are to be screwed down and impair the grip of the screw and the sealing of the joint. Following the insertion of the screws, the strip is lost, is prejudicial when working and must be consequently removed again from the site.
In addition, apparatuses with an individual screw supply have been proposed, in which for supply purposes the screws have to be manually thrown into a shaft. Such apparatuses do not make it possible to work on vertical walls or overhead.